Rename most of the configuration from EventStore to KurrentDB, while still accepting configuration provided with EventStore prefixes and files. The benefit of using separate ConfigurationProviders for this is that it is easy to discover which options are still using the legacy prefix, and they're logged automatically at startup. e.g.:

MODIFIED OPTIONS:
    APPLICATION OPTIONS:
         CONFIG:                          /etc/eventstore/eventstore.conf (Event Store Default Locations Provider)
         WORKER THREADS:                  5 (Event Store Environment Variables)

    CLUSTER OPTIONS:
         NODE PRIORITY:                   6 (Event Store Command Line)

    INTERFACE OPTIONS:
         NODE PORT:                       1111 (Yaml)

Changes to configuration options:

• Rename EventStore prefixes and config sections to KurrentDB.
• Add legacy EventStore sources and providers which load any options provided with the EventStore prefix and transform the prefix to KurrentDB:
  • EventStoreEnvironmentVariables*
  • EventStoreCommandLine*
  • EventStoreJsonFile*
• Log a deprecation warning when an option is provided with the EventStore prefix:

The "EventStore" configuration root has been deprecated and renamed to "KurrentDB". The following settings will still be used, but will stop working in a future release:
"Licensing" Provided by: Event Store Environment Variables. The "EventStore" configuration root has been deprecated, use "KurrentDB" instead.
"NodePort" Provided by: Event Store Command Line. The "EventStore" configuration root has been deprecated, use "KurrentDB" instead.

Changes to default locations:

• Rename default locations from eventstore to kurrentdb.
• Rename default config file from eventstore.conf to kurrentdb.conf.
• Add EventStoreDefaultLocations* config provider and source which overrides some default locations if the EventStore locations exist and the KurrentDB locations do not. This only works for the following locations:
  • The default config file /etc/kurrentdb/kurrentdb.conf -> /etc/eventstore/eventstore.conf
  • The default data directory /var/lib/kurrentdb/ -> /var/lib/eventstore/
  • The default log directory /var/log/kurrentdb/ -> /var/log/eventstore/
• Log a deprecation warning when using an EventStore default location rather than a current one:

"KurrentDB:Config": The default location "/etc/kurrentdb/kurrentdb.conf" was not found, using the legacy default location "/etc/eventstore/eventstore.conf".
"KurrentDB:Db": The default location "/var/lib/kurrentdb" was not found, using the legacy default location "/var/lib/eventstore".
"KurrentDB:Log": The default location "/var/log/kurrentdb" was not found, using the legacy default location "/var/log/eventstore".